DR Congo's top court on Sunday declared opposition leader Felix Tshisekedi the winner of disputed presidential elections after throwing out a legal challenge by the runner-up.
Announcing the final results of the long awaited poll, the Constitutional Court said Tshisekedi had won by a simple majority, paving the way for him to take over from longterm leader Joseph Kabila in an official ceremony on Tuesday.
Runner-up Martin Fayulu immediately called on the international community to reject the results, after the court said his appeal was "unfounded".
"I ask the entire international community not to recognise a power that has neither legitimacy nor legal standing to represent the Congolese people," he said of Tshisekedi, declaring himself "the only legitimate president".
Tshisekedi's victory was first announced earlier this month based on provisional results by the Independent National Election Commission (CENI) but it was challenged both at home and abroad, with the African Union appealing for the final results to be delayed.
On Sunday, the Constitutional Court said Fayulu had failed to prove any inaccuracies.
"Only the CENI has produced authentic and sincere results," judge Noel Kilomba said.
Hundreds of supporters of Tshisekedi had gathered outside the court holding placards saying "No to interference" and "Independent country" as riot police stood nearby.
The election commission announced on January 10 that Tshisekedi had provisionally won with 38.57 percent of the vote against Fayulu's 34.8 percent.
Fayulu denounced the figures as an "electoral coup" forged by Tshisekedi and Kabila, and filed an appeal with the Constitutional Court.
At a summit on Thursday, AU leaders said there were "serious doubts" about the vote's provisional results and called for the announcement of the final results to be suspended.
But DR Congo government spokesman Lambert Mende had snubbed the demand, saying: "I don't think it is the business of the government or even of the African Union to tell the court what it should do."
The AU also announced that its commission chief Moussa Faki Mahamat and Rwanda's President Paul Kagame, currently the AU chairman, were expected to fly to DR Congo on Monday.
The European Union said it joined the AU in inviting "all the Congolese players to work constructively with this (AU) delegation to find a post-electoral solution which respects the Congolese people's vote".
The Financial Times and other foreign media have reported seeing documents that confirm Fayulu as the winner.
"If the court declares Tshisekedi victor, the risk of isolation would be enormous and untenable for a country positioned right in the middle of the continent," Adeline Van Houtte of the Economist Intelligence Unit wrote on Twitter.
Fayulu's camp had hailed the AU appeal for the final result to be put on hold, but Tshisekedi's entourage branded it "scandalous".
The dispute has raised fears that the political crisis that began when Kabila refused to step down at the end of his constitutional term in office two years ago, could turn into a bloodbath.
The vast and chronically unstable country lived through two regional wars in 1996-97 and 1998-2003, and the previous two elections, in 2006 and 2011, were marred by bloody clashes.
The AU has taken the firmest line of all major international bodies with regard to the post-election crisis.
The Southern African Development Community (SADC), a bloc that includes Angola and South Africa, initially called for a recount and a unity government.
But in a later communique, it made no mention of those demands, instead calling on Congolese politicians to "address any electoral grievances in line with the Democratic Republic of Congo's Constitution and relevant electoral laws".